Various types of optical fiber connectors are known for connecting two optical fibers. One type of such connectors is a pair of plugs with each fixed to an end of an optical fiber. These connectors may also include an adapter through which the optical fibers are interconnected with the optical axis of the plugs aligned. Umeki, et al, Japanese Showa 60-218932 discloses a push-pull coupling type of connector. It includes an adapter equipped with an alignment sleeve and resilient catch pieces. The pieces are in cantilever form with protrusions and a claw attached to the tip of the form. The connector also includes a frame that contains an integrated ferrule and a through passageway from the rear to the front of the ferrule. The frame has protruding parts that are caught by claws of the resilient catch pieces of the adapter. A resilient inner tube shaped in the form of a round tube has an inside diameter almost equal to the outside diameter of the optical fiber cable and an outside diameter almost equal to the hole in the rear portion of the plug frame. A cord tube has a flexible part at its front end which, when inserted into the hole in the rear of the plug frame, is secured to the frame by the bending of the flexible part. The plug frame also has a finger grip mounted on its outside with raised parts. When the ferrule of the plug frame is inserted into or pulled from the alignment sleeve, the raised parts of the plug frame contact the protrusions of the cantilever form and push the resilient claws to the outside allowing the protrusions to pass. The plug frame may have a finger grip housing which is able to slide forward and backward with respect to the plug frame and, additionally, which has raised parts which release the catch of claws on the protruding parts of the plug frame when the finger grip housing is moved backward.
The present invention relates to an active device mount (ADM) assembly with interface mount for disconnect connection of an active device to an optical fiber of the push-pull coupling type of connector such as disclosed by Iwasa, et al, Japanese Showa 62-26141; Kaihara, et al, U.S. Pat. No. 4,762,389; and Myers, et al, U.S. Pat. No. 4,872,736. Particularly, the invention relates to an active device mount (ADM) assembly for the push-pull coupling type of connector disclosed by co-pending patent application Ser. No. 491,755 filed Mar. 9, 1990. With ADM assemblies, optical emission from, for example a diode, or an optical signal to a detector, as the case may be, is transmitted successively through different transparent materials having different indices of optical refraction. A difficulty associated with conventional connector assemblies is that the light signal is scattered at the boundary between transparent materials of different indices. Another difficulty is that the light signal may reflect from surfaces of the materials or from a junction of one of the materials with an air gap. Particularly, if the active device is a laser diode, and the emission is reflected backward at low angles of incidence to the reflecting surface, such backward reflection can enter the laser diode and cause instability.
An advantage of the present invention resides in an ADM assembly which permits disconnect coupling of a push-pull coupling type optical fiber connector to an active device with substantially reduced backward reflection. Further, the ADM assembly is advantageous in providing a mount for optical fiber connectors of the push-pull coupling type where heretofore, no such device mount assemblies existed and it was required that such push-pull coupling type optical fiber connectors be connected to active devices through modifications of existing mounts with results which, at best, could be described as workable. According to the present invention, an ADM assembly provides a disconnect coupling for a push-pull coupling type optical fiber connector to an active device with the same accuracy of alignment as the coupling of an optical fiber to an optical fiber while eliminating backward reflection and unnecessary loss.